Growth should probably be more precisely defined in the vast majority of cases to avoid confusion and misunderstanding. In terms of systems, the quantity that

Growth should probably be more precisely defined in the vast majority of cases to avoid confusion and misunderstanding. In terms of systems, the quantity that grows or shrinks should be concrete (i.e. not a rate, certainly). For example, human population. Let's say the birthrate in a population is growing, so a naive conclusion would be that the population, a concrete object, must also be growing. This is not true if the deathrate is growing by the same amount. Now, this is the standard kind of thing you see in a intro to differential equations course: a river feeds a lake at rate X, and another river drains a lake at rate Y, and so is the lake growing or shrinking? Ooops, we neglected to take evaporation into account, so we get the wrong answer. Economists are among the worst offenders in this misuse of concepts. Take 'productivity growth' - this is actually growth in the rate at which product is produced, right? If productivity is flat and market demand is flat and human population is flat, well, that means everyone is getting what they need, if say the product is cell phones, for example. If everyone has a cell phone, and cell phones are replaced every five years, then what is productivity growth? Maybe you can make the cell phone manufacturing line more efficient, by recycling the materials from old cell phones into new cell phones, or by automation etc. Nevertheless, the desired rate of cell phone production is fixed, and everyone has a cell phone. Of course the market should be broken up between different producers to encourage competition, but here growth in production of a better cell phone with higher demand is counterbalanced by shrinkage in market share by another producer, as net demand is flat. Unfortunately, if the cell phone makers form a cartel, and raise their prices in unison, some economist will call that 'economic growth' based on the fact that they're extracting more money from a market with fixed demand, which is just ludicrous - but that's modern neoclassical economics for you.